UDC 629.118.6.011 : 672.658 IS : 11740-1986 - t- Indian Standard ( Reaffirmed 2006 ) SPECIFICATION FOR CHAINS MOTORCYCLES FOR . Scope -Covers the requirements for chains for use with motorcycles. Chains for motorcycles ccording to their uses, comprise drive chains (for driving a rear wheel ), cam chains (for driving can `hafts). balancer chains (for driving balance shafts) and chains for driving miscellaneous equipment !. NomenclatureTABLE 1 Shall be as given PARTS, in Table THEIR 1 read with Fig, AND 1) 1. CONSTRUCTION 1 CHAINS NOMENCLATURE 2 and 5; and Fig. (Clauses clature Outer link An outer assembled link consists of two pin: with two outer plates. j Inner link An Inner link consists of two roller: around two bushes assembled with two Inner plates. Spring clip type connecting link Connecting Connecting pin plate A sprmg clip connecting link consists of two connecting pins press fitted ir an outer plate and rlvetted. At the other ends they are either a press-fil or a slip-fit in a connecting plate and secured by a spring clip. press fitted in a connecting secured by nveting. plat l Chain numbers 25H, 219 and 270 are rollerless. Adopted 16 July, 1986 I BUREAU MANAK 0 February 1988 8IS Gr 4 8HA"AtF 9 tiEW l&%$RN DELHI STANDARDS SHAH ZAFAR 110002 MARG IS: 11740-1986 OUTER INNER LINK LINK INNER PLATE OUTER PLA&/ AOLLCR FIG. 1 CHAIN h ASSEMBLY 3. Designation -Chains numbers given in Table for motor cycles specified in this standard 2 with their main application. shall be designated by chain TABLE 2 CHAIN NUMBER AND MAIN USES OF CHAINS Chain Number Cam Cam Drive Drive Used Mainly chain chain, chain chain chain chain chain chain balancer As Remarks Bush chain Bush Bush Roller Roller Roller Roller Roller chain chain chain chain chain chain chain chain 25 H 219 270 420 428 520 H M Drive Drive Drive Drive 50 M 630 Note-Chains 2 means CbSS are designed to conform to the most popular chain numbers. The first digits express the pitch size. SJ that between 6.35 mm and 9.525 mm; 4, 12.70 mm; 5, 15.875 mm; 6, 19-05 mm respectively. Suffix M means middle and suffix H, high class. 4. Form and Dimensions given in Table 3. - Chains shall conform to the form shown in Fig. 2 and the dimensions FIG. 2 CHAIN FORM AND DIMENSIONS 2 IS : 11740-1986 TABLE 3 CHAIN DIMENSIONS (Clause 4; and Fig. 3) in millimetres. All dimensions Chain No. Pitch P Roller Diameter dl Max Width Between Inner Plates bi Min Pin . `Length b4 Max Diameter' dl Max (Reference) Part of Connecting Pin Length I Inner Plate Depth hz Max Plate Thickness (Rnfeience) Max 5.0 7.3 7.8 9.0 11.6 10.9 12.5 13*5 25 H 219 270 420 428 H 520 M 50M 630 "These 6-35 7.774 8.50 12.70 12.70 15,875 15.875 19.05 dimensions 3.30" 4.59" 5.00" 7-77 8.50 10.16 10.16 11.91 of d, are for a bush 3.10 4.68 4.75 6.25 7.85 6.25 940 9.40 diameter. 9.0 12.0 13.3 14.8 18.9 17.6 20.8 33.2 2.31 3.01 3.28 3.97 4.51 5.24 5.24 5.96 6-O 7.6 8.0 12.0 12.5 15.0 15.0 18.6 1.0 1.2 1.6 1.5 2.0 2.0 2.0 2.4 4.1 This standard does not stipulate sprocket dimensions necessary for sprocket marking dimensions but Appendix A describes chains to actuate correctly. how to calculate 5. Chain Construction-A illustrated in Fig. 1. A chain, a bush chain. chain is assembled with inner links and outer links alternately, as which holds rollers around bushes, is called a roller chain and rollerless, To connect chains, connecting links are used and offset links are not recommended, as a rule. As Table 1 shows, there are two kinds of spring clip type connecting links and two kinds of rivetted type connecting links, total four kinds. Connecting links should be avoided unless manufacturers recommend them since connecting links are generally weaker than regular links in fatigue strength and the pushout force of a pin from a * connecting plate. 6. Tests 6.1 Breaking Load-A tensile load shall be applied slowly up to failure to the ends of a chain length, containing at least five free pitches, by means of shackles preventing it from twisting, bending, etc, and the ultimate tensile load shall be measured. Note as the Strictly speaking, a breaking load means a load when a chain has failed, breaking load in this standard on account of their small difference. but the ultimate tensile load is regarded The minimum breaking loads of chains shall be those given in Table 4. TABLE 4 BREAKING (Clause 6.1 LOADS ) Breaking Load kN, Min 4.8 6.6 9.8 15.7 Chain Number 25 H 219 270 420 428 520M 50M 630 H 20.6 26.5 26.5 35.3 length, not less than 610 mm, of a finished chain before 6.2 Length Accuracy - A standard lubricating, shall be measured by means of shackles under the measuring load given in Table 5. When being measured horizontally, a chain shall be loaded, being supported horizontally throughout its entire length. 3 IS:11740-1986 TABLE 5 MEASURING (Clause Chain Number LOAD 6.2 ) Measuring Min N 80 80 80 140 Load 25 H 219 270 420 428 520M 50M 630 H 140 220 220 310 6.2.1 nominal The chain length shall be the nominal length subject to the tolerance length being calculated as nominal pitch (p) multiplied by number f0.15 percent of links. the by in 6.3 Fatigue Strengrh -The fatigue strength of chains is evaluated with the fatigue limit obtained the testing method described in Appendix B. The level values of fatigue limit shall be as shown Table 6. 7. Inspection -Chains shall be inspected for breaking load and length accuracy test is a type test and shall not be carried out as a routine test. 8. Rust Prevention -Chains other suitable treatments. 9. 9.1 Marking -All chains Markingshall be applied with with rust preventives but fatigue from strength rusting by or prevented shall be marked Details manufacturer's with name (or trade-mark) of on outer plates. Certification available the Bureau Indian Standards. TABLE 6 LEVEL VALUES (Clause OF FATIGUE 6.3) LIMIT A- TIME Level Value Fatigue Limit 980 1080 2 260 3 730 of in N Chain Number 25 H 219 270 420 428 H 4410 7 360 7 360 9810 without any connecting link 520 M 50M 630 Note 1 -All values above are for chains Note 2 -When a repeated load in which the ratio (Pm/Pa) of a mean load (Pm) to a load amplitude (Pa) is equal to l-2 is applied to a chain, the fatigue limit of the chain shall be the highest load among loads, which do not cause chain farlure before repeated number of 5 X 10h. The details are given in Appendix 8. Note 3 -As shown in the above figure, a sum (Pm is called a maximum load (P Max). The fatigue Note 4-The level values in Table 6 show + Pa) of a mean load (Pm) and a load amplitude (Pa) limit is represented wrth a maximum load obtained aim and are not to regulate the lower of a repeated by 2 above. limit loads toad an approximate IS : 11740-1986 APPENDIX (Clause SPROCKET A-l. Sprocket standard dimensions with A 4.1) to Fig. 3 shall be calculated as follows: CHARACTERISTICS respect FIG. 3 SPROCKET CHARACTERISTICS Item Calculation -P Formula Pitch circle diameter(d) d = . 180° sin __ z Jop diameter (&) 180" d,., = p (0.6 + cot --) -' Root diameter (d,) d, = d d, d, number ri, of teeth) (Odd number of teeth) = L/, (Even Caliper distance (do u', = d cos 90" z I =P 180" 2 sin 2~ ~ - d, Tooth width ( brl) h,, = 0.93 h, = 0.95 h, (p < (p > 12.70) 12.70) Here p = chain pitch, d, = chain roller diameter, 6, = chain width between z = number of teeth. Note-p, d, and b, -As inner plates, in Table and 3. given 5 IS : 11740-1986 1 sin shown Number of Te;th sin 180" ' A-2. Calculated values of ~ for every number of teeth. are below:' 1 180" Z 1 180" 2sin-,LZ cot ~ 180" L Number of Teeth 2 39 40 44: 43 44 45 46 t; 49 50 51 52 E! 55 z; 58 59 60 6": 66: 65 I . 180" sinZ I 2sinF 12.417-4 13.053.9 3.690.4 1 4.226.9 1 4.963.4 - eot180" Z 3.549.5 3.863.7 4.178.6 4.494.0 4.809.7 5.125.8 5.442.2 5.758,.3 6.075.5 6.392-5 6.709.5 7.026.7 7.343.9 7.66 1 a3 7.978.7 8-296.2 8.6 13.8 8.93 I.4 9.491. 9.566.8 g-884.5 10.202.3 10.520*1 10.838.0 11 .I 55-8 1 1.473.7 11.791.6 12.109.6 3.513.3 4.148.1 4.783.4 5.419.0 6.054.8 6.690.7 7.326.8 7.963.0 8.599.2 9.235.5 9.871.8 10.504.2 11.144.6 ll%WO - 3,406 3.732 4.057 4.381 4.705 5.027 5.350 5.671 5-993 6,314 6-635 6.955 7.276 7.596 7.916 8.236 8.556 8.875 9.195 9.514 9.834 10.1.53 10.472 IO.792 11.111 11.430 11.749 12.068 12.427.5 12-745.5 13.061.5 13.381.5 13.609.5 14.017.5 14.335.6 14.653-6 14.971.7 15.289-8 15.607.9 15.926.0 16.244.1 16.562.2 16.880-3 17.198~4 17.516-6 17.834.7 18.155.9 18.471.0 18.789-2 19.107-3 19-425.5 19.743.7 20,081*8 20.3800 20.698.2 12.387 12.706 1 3.025 3.349 3.664 3.982 4.301 4619 1 4.938 15.257 15.576 15.696 16.231 16.532 16.851 17,169 17.488 17.807 18-125 18.444 18.763 19.881 25.599.6 16.236.4 16.872.9 17.509.4 18.146.0 18.782.5 19.419.0 20.055.6 20.692.2 19.400 19-718 20.037 20-365 20-674 APPENDIX (Clause FATIGUE B-l. Chains for Test - Chains through all normal processes B-2. Testing immediately a) An Machines -A and constantly, of the STRENGTH B 6.3) TESTING FIXTURE which have been manufactured in 6.3, submitted and have to the test should be those passed all inspection. is to be able to impose to have the following chain and testing machine and preferably load applied a repeated auxiliary of the load specified equipment: repeated load; indicator to the a counter again after b) A device to prevent the testing machine from break in the electricity supply, etc; and c) An automatic stoppage device starting B-31. an emergency stop due to a [refer to ( g ) of B-2.1 The repeated agreement between speed of a testing machine shall be 500 to 3 000 the supplier and the purchaser. 6 rpm, except in cases of mutual IS:11740-1986 B-3. Testing Method 5 to 7 free pitches excluding those for shackles. Figure 4A and a) A chain for test shall contain 4B show 5 free pitches. b) A chain for the test shall be fixed to the shackles of a testing machine so carefully tensile loaded evenly on every link and not subjected to twisting, bending, etc. reach starting a test, a testing machine should be controlled immediately an intended load, avoiding any shock or overload from the range. a test on one chain, the shall after test, as a rule, after number shall the not stop during loading has the been as to be to cl When and carefully the process. 4 f) 9) h) j) During e) Repeated When A testing recorded. A series times, as a rule, does not fail be counted repeated when shall completed. be stopped. shall then be speed. a chain 5 X 106, test should number machine of tests stops automatically, for an S-N curve a chain fails, The repeated be furnished under a constant repeated When making an S-N curve loads are designed in a way that the ratio of the neighbouring two loads shall be 1.05 to 1.5 along a slope of an S-N curve and 1.02 to 1.15 around the fatigue limit. ROLLER - 4A FIG. 4 CHAINS UNDER FATIGUE TEST B-4. Treatment of Tested Results 48 a) Maximum loads and repeated times shall be rounded off to three IS : 2-1960 `Rules for rounding off numerical values (revised)`. significant figures, as per b) An S-N curve is drawn through tested points marked on the coordinate which takes maximum load on the axis of ordinate with the ordinal or the logarithmic scale and repeated times on the axis of abscissa with the logarithmic scale and tested points without failure shall be marked with an arrow toward the right. 7 IS : 11740-1986 c) Suppose that a first repeated load at which a chain has not failed before repeated number of 5 X lo6 is found after repeated loads have been getting smaller, than a middle load between this first repeated load and the lowest repeated load among those with which chains have failed, should be applied to a chain. Here on, when the chain does not fail before repeated number of 5 X IO a maximum load of this middle load is the fatigue limit, and when the chain fails, that of the first load is the fatigue limit. Example: Suppose that a first chain fails before repeated number of 5 X IO" with a repeated load, a maximum load of which is 12 000 N, and that the second chain fails also with that 10 000 N and suppose again that the third chain does not fail, before repeated number of 5 X IO" with a repeated load, a maximum load of which is 8 000 N. Then the middle load between 10 000 N and 8 000 N, that is, 9 000 N should be applied to the fourth chain. Hereon, when the fourth does not fail, the fatigue limit is 9000 N, and when the fourth fails, it is 8000 N. Generally, it takes a considerably long time to carry out a fatigue test to obtain the fatigue strength of statistically consistent values, because it takes a long time even to get one point on an S-N curve and moreover, those points have a wide variation. Such efforts do not seem suitable for massproducing factories. Therefore, such a concise chain fatigue testing method as even they can practise, has become to be desired. As a result, the fatigue limit has been decided to be obtained through such a concise procedure as (c) of B-4, and also these values are almost proper to evaluate the quality. Under the above mentioned conception, testing method of chains for fatigue strength has been composed. The reason why the standard takes a repeated load as the ratio (Pm/Pa) of a mean load (Pm) to a load amplitude (Pa) is equal to 1.2, is that the chain is loaded by 20 percent of the load amplitude (Pa) even at the minimum load (P /Win), because chains can not be compressed. On an axis of ordinate of an S-N curve, a maximum load is adopted, because it is to be more understandable than twice a load amplitude which is recommended to be adopted by some members. Accordingly, a fatigue limit is represented with a maximum load of the repeated load EXPLANATORY Among the chains 1975 `Transmission this standard. NOTE for motorcycles those which are almost the same as several chains in IS : 2403steel roller chains and chain wheels (first revision)' have been excluded from Silent chains, sealed chains and oil impregnated steel bush chains are still under development and other special chains are.not yet universally adopted, therefore these chains may be standardized in future. Testing method found in future. In preparation 1) JCAS 1-1981 for fatigue of this strength of chains may also be revised assistance Chain for has been Association as soon as a better derived Standard from the rnethod following: is standard for considerable Chains ~~torcYckS. Japan Chains ( JCAS). Organization for 2) DOC : ISO/TC Standardization 100 (Japan) ( IS0 ). N 169 motorcycles, International 8